Thursday, 28 March, 2024
HomeCoronavirusCOVID-19's cognitive cost may be equivalent to 10-years ageing — UK intelligence...

COVID-19's cognitive cost may be equivalent to 10-years ageing — UK intelligence test data

A non-peer-reviewed study of more than 84,000 people, led by Adam Hampshire, a doctor at Imperial College London, found that in some severe cases, coronavirus infection is linked to substantial cognitive deficits for months. “Our analyses … align with the view that there are chronic cognitive consequences of having COVID-19,Reuters Health reports the researchers wrote in a report of their findings. “People who had recovered, including those no longer reporting symptoms, exhibited significant cognitive deficits.”

Cognitive tests measure how well the brain performs tasks – such as remembering words or joining dots on a puzzle. Such tests are widely used to assess brain performance in diseases like Alzheimer’s, and can also help doctors assess temporary brain impairments.

Hampshire’s team analysed results from 84,285 people who completed a study called the Great British Intelligence Test.

The cognitive deficits were “of substantial effect size”, particularly among people who had been hospitalised with COVID-19, the researchers said, with the worst cases showing impacts “equivalent to the average 10-year decline in global performance between the ages of 20 to 70”.

Scientists not directly involved with the study, however, said its results should be viewed with some caution.

“The cognitive function of the participants was not known pre-COVID, and the results also do not reflect long-term recovery – so any effects on cognition may be short term,” said Joanna Wardlaw, a professor of applied neuroimaging at Edinburgh University.

Derek Hill, a professor of medical imaging science at University College London, also noted that the study’s findings could not be entirely reliable, since they did not compare before and after scores, and involved a large number of people who self-reported having had COVID-19, who had no positive test.

“Overall (this is) an intriguing but inconclusive piece of research into the effect of COVID on the brain,” Hill said.

“As researchers seek to better understand the long-term impact of COVID, it will be important to further investigate the extent to which cognition is impacted in the weeks and months after the infection, and whether permanent damage to brain function results in some people.”

Abstract
Case studies have revealed neurological problems in severely affected COVID-19 patients. However, there is little information regarding the nature and broader prevalence of cognitive problems post-infection or across the full spread of severity. We analysed cognitive test data from 84,285 Great British Intelligence Test participants who completed a questionnaire regarding suspected and biologically confirmed COVID-19 infection. People who had recovered, including those no longer reporting symptoms, exhibited significant cognitive deficits when controlling for age, gender, education level, income, racial-ethnic group and pre-existing medical disorders. They were of substantial effect size for people who had been hospitalised, but also for mild but biologically confirmed cases who reported no breathing difficulty. Finer grained analyses of performance support the hypothesis that COVID-19 has a multi-system impact on human cognition.

Authors
Adam Hampshire, William Trender, Samuel R Chamberlain, Amy Jolly, Jon E Grant, Fiona Patrick, Ndaba Mazibuko, Steve Williams, Joseph M Barnby, Peter Hellyer, Mitul A Mehta

 

[link url="https://uk.reuters.com/article/us-health-coronavirus-brains/covids-cognitive-costs-some-patients-brains-may-age-10-years-idUKKBN27C1MV"]Full Reuters Health report[/link]

 

[link url="https://www.medrxiv.org/content/10.1101/2020.10.20.20215863v1"]MedRxiv abstract[/link]

MedicalBrief — our free weekly e-newsletter

We'd appreciate as much information as possible, however only an email address is required.